The arrangement of sound production speaker units in existing headphone products mainly uses conventional matrix arrangement in general. It is required to conduct the sound of the speakers of the headphone into the ear in the design of a headphone, and therefore, the shapes of the front cavity parts of all headphones are like a funnel. However, the funnel-shaped structure causes a bottleneck with a wide upper part and a narrow lower part to the matrix-arranged speakers, thus affecting the overall sound transmission efficiency.
For example, for the speakers directly facing a funnel-shaped outlet, because the speakers and the sound output opening are connected in a line, the sound transmission distance is the shortest and the sound transmission efficiency is the highest; while for the speakers arranged at two sides, because of the shape of the front cavity with a wide upper part and a narrow lower part, a local deformation is caused, thus achieving a different effect. The effect may be an increased sound transmission distance, and may be a sound attenuation or individual frequency effect caused by a decreased and deformed transmission space. Therefore, the sound performance consistency of the speakers is poor, and the maximum or ideal effects of the respective speakers cannot be achieved.
For some headphone products where a plurality of speakers are built in, in the inner structure, an independent sound-conducting pipe made of a soft or hard material is configured for individual speaker units or speaker groups, the individual speaker or the speaker groups are connected by independent pipelines with a particular size, and the sound of all the speakers is concentrated to the sound output opening of the front cavity of the headphone by the pipeline, so as to satisfy sound transmission requirements of different speakers. FIGS. 1 and 2 show schematic diagrams of the boundary structures of the inner structures of two conventional headphones. The headphones in the schematic diagrams each comprise a plurality of speaker units 10 (three speaker units, i.e., speaker units 1, 2 and 3, in the schematic diagrams), which are arranged in the headphone. During sound production, the sound transmission is affected due to an inner arrangement problem. For example, for the regions 110 in the schematic diagrams, because of the difference in the shapes thereof, an obvious local deformation is caused, thus different effects are caused to the sound transmission, and the effects of the transmitted sound are not good.
However, the lengths or shapes of the independent pipelines are not the same, thus different effects are also caused to the individual speakers or the speaker groups. For instance, the inner spaces of straight and bent conductor pipes are not the same. In the same speaker group, individual speakers share a straight range and individual speakers share a surrounding range. Different effects are also caused to speakers under the limitation of the different overall ranges of the conductor pipes when the same group of speakers performs transmission. The sound transmission efficiency of individual speakers may be greatly reduced if the edges of the pipelines and the speakers form narrow ranges. In addition, the design of using independent conductor pipes is limited by the overall size of the individual speakers, while more speaker units cannot be increased in the cavity of the headphone, thus improving the overall effect. For example, for the front cavity of a circular speaker with an inner diameter of only 5 mm, physically, it is impossible to use a conductor pipe with an outer diameter of 5 mm or more. That is to say, the original effective sound transmission space and route of the front cavity with the inner diameter of 5 mm is limited by the size of the independent pipelines, so as to reduce the original transmission space, thus greatly reducing the transmission efficiency.
Therefore, it is urgently required to improve the prior art, so as to obtain a transmission structure having high transmission efficiency and a good sound effect, thereby satisfying the spiritual life requirements of people.